Mercruiser 351W bangs going in to gear..

[loadnet]

This is a Pre-Alpha 1 drive mounted to a 351W in a 24' Searay.<br /><br />Always goes into gear and the noise has not increased at all over the summer but I have to say, the bang when it goes into gear sure is louder than I'd like to hear it shift.<br /><br />Anyway to quiet this thing down?<br />My transom is solid all around the gimbal.<br />A little weak up in one corner...<br /><br />Sounds like a loud CLUNK every shift no matter what.<br /><br />Idle is at 550 to 700 RPM prior to shifting.<br /><br />Do you think my interupter switch could be bad? and if so, how can I check it out to prove it's junk?<br /><br />Thanks in advance to anyone that replies.<br />Direct Email to me is: customerservice@401hosting.com

 

[Skinsk]

Re: Mercruiser 351W bangs going in to gear..

A fairly loud "clunk" going into gear is normal for all alpha, and pre-alpha drives.<br /><br />Scott..

 

[Northern Eclipse]

Re: Mercruiser 351W bangs going in to gear..

CHF They do Clunk pretty hard, if the shift interrupt was going bad then is should be more difficult to shift into neutral, I also thought that my alpa one had a loud clunk in My Wellcraft, I cured the loud clunking by installing thru hull exhaust.....seriously as long as its not grinding or clanging once in gear should be fine, But if you think that drive has a more pronounced clunk than it once had then that could be a early sign for shift cable adjustment or replacement

 

[Bondo]

Re: Mercruiser 351W bangs going in to gear..

A Brisk Shift,+ a Loud Clunk is the sign of a Good Running Alpha1 or Mod.1<br /><br />If your Idle is 550/600rpms, That's Good... <br />700rpms is getting a little on the high side....

 

[loadnet]

Re: Mercruiser 351W bangs going in to gear..

The boat shifts fine going in and out of gear..<br /><br />Everyone keeps telling me that's a normal sound and don't worry about it but something just isn't right there..<br /><br />Do you guys know the test for the interupter switch other than looking at it when in forward gear to make sure it's at the very bottom of the valley?<br /><br />Can't that be tested with an ohm or volt meter somehow to make sure that baby is doing it's job correctly?<br /><br />PB

 

[loadnet]

Re: Mercruiser 351W bangs going in to gear..

NE.... how did thru hull exhaust manage to stop your loud clunk when shifting?

 

[Skinsk]

Re: Mercruiser 351W bangs going in to gear..

The interupter switch is to burp the motor coming out of gear. The motor needs to be burped in order for the undercut gears to be able to release. The interupter switch has nothing to do with going into gear, except when the shift cable is worn, and then it stalls the motor.<br /><br />You can completely disconnect the interupter switch, and the motor with go into gear just the same, but when you try to take it out of gear, you'll probably have to put your foot on the dash and pull. <br /><br />Scott..<br /><br />and.. if you have a stainless prop, or a high pitch prop, the bang can be even louder..

 

[loadnet]

Re: Mercruiser 351W bangs going in to gear..

SKINSK<br /><br />thanks for bringing the prop pitch to my attention.<br /><br />Mine is a 12 pitch prop so I'm sure that's contributing to the loud bang, trying to grab a whole bunch of water when tossed into gear.<br /><br />Bondo<br /><br /> I'm shifting this thing real brisk, and it shifts beautiful.. no problem there, that's why I can't figure this kinda extra loud clunk going in to gear either forward or reverse.. same clunk.<br /><br />Coming out of gear is just fine.. no strain no pain...<br /><br />I also have NO insulation under my engine covers and they are made out of marine 5/8ths plywood, like hard as a rock, so maybe they are also contributing to amplify the noise a bit eh?

 

[Northern Eclipse]

Re: Mercruiser 351W bangs going in to gear..

CHF With straight pipes going strait out the back the only thing I hear now is my exhaust noise.....

 

[loadnet]

Re: Mercruiser 351W bangs going in to gear..

NE.... Now I'm gettn wit yEr saying.<br /><br />Have you seen those elbow thingys they bolt to the back of the transom which accepts your exhaust thru hull and directs the noise down under the back of the hull, like straight down?<br /><br />I would think that would do a bang up job of quieting down the exhaust noise and at the same time give the unit more lift at take off!<br /><br />Toss some of that stuff that kids use to blow bubbles in the carb at lift off and you could have one heck of a show going on out there behind your boat eh?